Salah Abdeslam, the prime surviving suspect in November's Paris attacks, has answered questions from Belgian investigators a day after his arrest but will fight extradition to France, his lawyer says.
Belgian prosecutors said Abdeslam and a second man arrested with him on Friday (local time) had been charged with "participation in terrorist murder".
"He is cooperating with Belgian justice," his lawyer Sven Mary told reporters outside the judicial police headquarters on Saturday, adding that Abdeslam, bedridden after being shot in the leg during his capture, admitted being in Paris on November 13.
His elder brother was among the suicide bombers involved in gun and bomb attacks that night that killed 130 people.
Mary added that the 26-year-old French national, who was born and raised in Brussels in a Moroccan immigrant family, would refuse the extradition demanded by French President Francois Hollande, who was in Brussels during Friday's drama.
Legal experts said his challenge was unlikely to succeed, but it would buy him more time to prepare his eventual defence.
Having spent his first night in captivity in a Brussels hospital, he is expected to be moved to a high-security jail in the western city of Bruges while legal proceedings continue.
French and Belgian leaders have hailed his arrest, several days after Brussels police stumbled on his fingerprints during a raid that turned violent, as a turning point in clarifying who planned and ordered the Paris attacks, in which all the identified assailants were shot dead or blew themselves up.
The arrest raises questions about the intelligence capabilities of the security services and the size of network Abdeslam could call on to conceal him for four months before he was found just a few hundred metres from his parents' home in the down-at-heel, North African quarter of the borough of Molenbeek.
A man using false papers in the names of Amine Choukri and Monir Ahmed Alaaj was also charged with terrorist murder.
A man in the house was charged with belonging to a terrorist organisation and he and a woman were charged with concealing criminals.
French Interior Minister Bernard Cazeneuve said after an emergency cabinet meeting that a trial could answer questions for those who suffered in the attacks.
"Abdeslam will have to answer to French justice for his acts," he said. "It is an important blow to the terrorist organisation Daesh (Islamic State) in Europe."
Friday's heavily armed swoop came after fake passports and Abdeslam's fingerprints were found following a bloody raid on Tuesday in which Mohamed Belkaid, a 35-year-old Algerian was shot dead and police officers wounded.
Hollande said Abdeslam's role in the killings was unclear, but investigators were sure he helped plan the operation for the Syria-based group.
There has also been speculation, associated with the finding of an abandoned suicide vest in Paris and the apparent panic of Abdeslam in calling friends to pick him up, that the younger brother had been meant to kill himself but changed his mind.